On a vote of 63 to 37, Kagan, who will succeed retired justice John Paul Stevens, became the second member President Obama has placed on the high court. One year ago, Sonia Sotomayor won confirmation as the court's first Latina.

Some Democrats have said they hope that the lifetime appointment of Kagan, a consensus-building liberal, will nudge the court slightly to the left.

Her confirmation is considered unlikely to immediately shift the court's ideology, however. Although she is expected to fit comfortably within the liberal wing of the court, she does not seem to be as liberal as Stevens was during his final years on the bench.

Along with her relative youth, Kagan, 50, brings a résumé unlike any of those with whom she will serve.

She will be the first appointee since 1972 to join the court with no judicial experience. Other justices have corporate law backgrounds or a long record of arguing before the court. Kagan worked briefly for a law firm and argued her first case before an appellate court 11 months ago. It happened to be before the Supreme Court, the first of six cases she argued as the nation's first female solicitor general.

Five Senate Republicans supported Kagan. One Democrat, Ben Nelson (Neb.), opposed her. Kagan watched the vote with her Justice Department colleagues in the solicitor general's conference room. Chief Justice John G. Roberts Jr. will swear her in at the court on Saturday.

Democrats hailed Kagan's legal acumen and suggested that her widely acknowledged charm might appeal to the critical swing vote of Justice Anthony M. Kennedy on the nine-member court. Of her career, Senate Majority Leader Harry M. Reid (D-Nev.) said: "She has brought people together of every ideological stripe."

Republicans criticized Kagan's lack of judicial experience and questioned whether she would adhere to "the rule of law." Senate Minority Leader Mitch McConnell (Ky.) called her "someone who has worked tirelessly to advance a political agenda."

Kagan will join Sotomayor and Justice Ruth Bader Ginsburg in the first bloc of three women serving on the court at the same time. Once she is sworn in, three Ivy League law schools -- Harvard, Yale and Columbia -- will have bragging rights as the alma maters of all nine justices.

Kagan's confirmation continues a period of remarkable change for the court; she is the fourth new justice in the past five years. The former Harvard Law School dean is replacing a 90-year-old legend who served longer than almost any other justice.

The experience Kagan brings to the court is from the political world of Washington. During her tenure as a policy adviser in the Clinton White House, she was deeply involved in the making of policy, not its legal interpretation, and was in the thick of administration efforts to craft legislative compromise, sway public opinion and count votes in Congress.